1. Field of the Invention
The present invention relates to computer networks, and, more particularly, to methods and apparatus for providing a user interface to access and manipulate files distributed over a computer network.
2. Art Background
In response to societal demand, computer networks have been proliferating rapidly in recent years. Such networks include local area networks (LANS) and wide area networks (WANS) comprising a number of computers that may communicate with one another. Apart from sending messages, this communication between networked computers allows programs to be run on more than one computer in a network. For example, an airline reservation service may present a user interface on a client computer while data input to the interface is transmitted to a server computer where a reservation database is accessed. This type of program execution, known as distributed programming, may be much more complicated than the above example but is nonetheless extremely common and efficient.
Distributed programs, however, are often written, developed and tested on different computers with different tools which are tightly bound to the particular machine upon which they operate and are integrated around language, computing platform or type of application. Continuing the above example, the graphic user interface portion may be developed on the client computer with a set of program tools for the Visual C++ programming language for PC Windows and a different set of tools for a graphic user interface (GUI) builder. Similarly, the reservation database may be developed on the server with a set of program tools from the C++ Workshop programming language running under Unix. Further, a program initially developed with a tool set, frequently may be redeveloped under a later version of the same tool set and possibly from a different manufacturer.
Thus, distributed programs present substantial difficulties to programmers since they must learn to operate the tool set that was used to develop each distributed tool segment. These tool sets are usually quite detailed and require days, weeks and even months to master. Further, to edit, view or debug the distributed program currently requires performing these functions under one tool set for a particular program segment, exiting the tool set, locating the tool set for a different program segment, which may be on a different computer, and entering that tool set. This type of operation is extremely time consuming, especially where a program has a large number of segments, each developed with a different tool set.
By employing a particular protocol, the World Wide Web has met the challenge of allowing users, through a single front end tool, to browse documents that reside on a large number of different platforms. The World Wide Web, however, which has been in existence for a number of years, does not provide for any other types of functions apart from browsing and thus the previously described problems presented by distributed programs remain.
Thus, there is a need for a system that provides the capability to develop distributed programs that operate on different computers, operating systems and communication protocols, while requiring only one set of tools. Further, there is a need for a system that allows such integration for programs that have already been partially developed or completely developed under a variety of tool environments and that require modification. More broadly, there is a need for a system that allows a single front end tool to perform operations on a plurality of files that reside on different platforms without requiring a user to separately access each separate platform specific piece on that platform. The present invention answers these and many other needs.
The present invention provides methods and apparatus for a front end navigating tool (the xe2x80x9cNAVIGATORxe2x80x9d) that may access and manipulate files distributed across different platforms. The front end navigating tool communicates with a plurality of server processes, resident on networked servers, to perform all types of file manipulations such as debugging and editing. The server processes communicate with gateway processes resident on the same machine as the calling server process that perform the desired function on any of a plurality of program segments that may be distributed across a plurality of computers.
Debugging is one example of a function that may involve distributed files. To service a debugging request, the navigator issues a request according to the URL protocol. Thus, a request is of the form: server type://machine/request, where server type is a protocol such as, for example, http or process, machine is the actual server address and request is the program or file that is requested. The appropriate machine and server process is then contacted by the navigator and provided with the name of the file, file A. The server process in turn selects the appropriate gateway process to perform the desired function. The gateway process attaches to the desired program, which is subsequently debugged. If the program calls a program on a different machine, the present invention provides a variety of mechanisms, transparent to the user, for allowing debugging to continue on the called program. In a preferred embodiment, the gateway process provides the server process with the address of the called program, file B. The server process notifies the navigator which then automatically assembles a request to the server process on the different host. The request is sent and the server process selects the appropriate gateway process which then attaches to the target program, file B. If file B returns to file A, then control is again passed to the navigator which calls file A as before except that the gateway process has maintained the appropriate address of the instruction after the call instruction to file B. Debugging then continues on file A.
Browsing, editing and any other function requests are similarly serviced through the front end navigator. A URL link contacts an appropriate server process resident on a target machine and the server process in turn selects the proper gateway process, which performs the desired function on the target file. The target file may include hypertext links to other files and functions may easily be performed on these files by clicking on the file names and then indicating a desired function. In this manner, users may efficiently access and manipulate distributed files through a single front end tool.